FIG. 1 illustrates a block diagram of the electrical components of a typical printed circuit board (PCB) motherboard 2 of a typical notebook computer. The motherboard 2 typically has several integrated circuits (ICs) mounted on it, such as, for example, a central processing unit (CPU) IC 3, a northbridge IC 4, a southbridge IC 5, an on-board graphics controller IC 9, a flash read-only-memory (ROM) IC 11, and a super input/output (I/O) IC 12. The motherboard 2 typically also includes several other components, such as memory slots 6, a graphics card slot 7, Peripheral Component Interconnect (PCI) slots 8, and busses 14-19. The CPU 3 is connected to the northbridge IC 4 by a front-side bus 14. The northbridge IC 4 is connected to the southbridge IC 5 by an internal bus 15. The northbridge IC 4 is connected to the graphics card slot 7 by a high-speed graphics bus 16. The northbridge IC 4 is connected to the memory slots 6 by a memory bus 17. The southbridge IC 5 is connected to the graphics controller IC 9 and to the PCI slots 8 by a PCI bus 18. The southbridge IC 5 is connected to the flash ROM device 11 and to the super I/O device 12 by a low pin count (LPC) bus 19.
The southbridge IC 5, the graphics controller IC 9 and the super I/O IC 12 have a plurality of I/O ports to which a plurality of electrical cables 21 may be connected in order to interface the motherboard 2 with external devices. For example, the southbridge IC 5 typically includes ports such as a Universal Serial Bus (USB) port, an Ethernet port, an audio coder/decoder (codec) port, a complementary metal oxide semiconductor (CMOS) memory device port, and other I/O ports. The super I/O IC 12 typically includes several I/O ports such as, for example, a serial port, a parallel port, a floppy disk port, a keyboard port, and a mouse port.
Docking stations and port replicators are apparatuses that are often used with notebook computers to enable the notebook computers to interface with external peripheral devices, such as, for example, display monitors, keyboards, mice, external disk drives, backup storage drives, printers, etc. When a docking station (not shown) or port replicator (not shown) is used with a notebook computer, the docking station or port replicator includes a connector that connects to a mating receptacle on the notebook computer. This connection interfaces the I/O ports of the southbridge IC 5, the graphics controller IC 9 and the super I/O IC 12 with electrical circuitry of the docking station or port replicator. Electrical cables are then used to connect the peripheral devices to the docking station or port replicator, thereby placing the peripheral devices in communication with the corresponding components of the motherboard 2.
The southbridge IC 5 includes a serializer/deserializer (SerDes) component (not shown). This component converts data that is in serial format into data that is in parallel format and converts data that is in parallel format into data that is in serial format. Because of the relatively large number of parallel I/O ports that are in the southbridge IC 5 and in the super I/O IC 12, the connector of the docking station or port replicator typically has a very high pin count (e.g., 150 to 200 pins). There are several disadvantages to such connectors. For example, connectors that have a large number of pins have large form factors, which means that the receptacle on the notebook computer and the corresponding contact area on the motherboard 2 are also relatively large in size. In addition, the large form factor of the connector and the accuracy with which the pins need to be aligned generally increase costs and reduce manufacturing yield. Furthermore, different parallel I/O connections on the motherboard 2 often have different data rate capabilities. However, all of these connections need to be designed to operate at the highest of these data rates. This results in over-engineering of the connections that would otherwise utilize lower data rates, which also leads to increased costs.
Accordingly, a need exists for a method and apparatus that enable the motherboard of the notebook computer to interface to a docking station or port replicator in a way that obviates the need for a connector that has a high pin count and a large form factor while also providing a high-speed communication link.